April WNS

Re: total rubbish

[ QUOTE ]
Nice application of the CA theory btw, but wasn't it mainly cost/efficiency (rather than quality/effectiveness) driven?

[/ QUOTE ]

Yes it was indeed, but the underlying principle applies here also, as it does to plasterer vs businessman and to YMI vs smart non-YMIs who know about boating. :-)
 
Re: VHF use to known targets

Ok.

These thing evolve thats why.

Remember in past times keeping a radar watch involved a watchkeeper/ master looking at a CRT down a scope in the dark and plotting with a chinagraph pencil.

Now multiple daylight units display all the data and bridge staff can watchkeep by glancing at the displays as they look out of the wheelhouse window / stroll down the bridge wing if available (and monitor VHF transmissions that address them personally)
 
Re: total rubbish

One important point of principle though, if I may. You set a lot of store by the fact a YMI agreed/invented the 90deg turn to starboard idea and so it must be more right than anything uttered by a non YMI. You ought to study the theory of comparative advantage before falling for that one. Summarising it hugely, "comparative advantage" says each person does (as a job) the thing that he or she does best, in the economic sense. So it is entirely feasible (in fact it happens) that folks who are smarter and cleverer and better boat navigators than a typical YMI do not become YMIs.

Aww, come on JFM.. he asked someone more knowlegeable than himself, and said thats what the trained person suggested, which must count for something, and I think its OK for Tony to have mentioned that it was YM (as opposed to who-knows-who) Many of us would prefer the added safety of heading north, but maybe thats a degree of safety that isnt necessary as the first step. After all, its up to the skipper. People here can make their own judgement, surely.
The point of these scenarios is to show possible solutions. Running parallel could be a viable solution, I reckon, depending on other criteria that you would judge at the time.
 
Re: total rubbish

HELP - Sorry to keep on about this but I am not a YM practical yet (have the theory) but want to take the exam later this year so this is of interest to me and I benefit from good advice from more experienced skippers.

So, can someone please explain to me again why a 90 or 180 to STBD is prefferable to an immediate and obvious turn to STBD to complete a 360? My analysis:

I have assumed that when one engine failed/overheated it was shut down and the skipper would then have altered course to get back to the nearest safe haven in the shortest possible time. He was then confronted with this dilema. So:

1) Port: Definately a no go for me, closing too fast on other boats who may have altered course to pass my stern.

2) Stop: Also a no go for me. Similar reasoning to 1) and I would need to keep a close eye on things so would not be able to do inspection, will have no immediate power to get out of trouble, my engines will be hot, I will be rocked to sleep when others pass.

3) 90-STBD: Safe, but then you are off course for quite a while as vessels close more slowly on you and you will take their waves on your beam or port quarter.

4) 180-STBD: Safe, but takes you in the opposite direction to that which you intended.

5) 360-STBD: Surely must be preferred. Safe, obvious to others, back on course in shortest time, take waves on bow.

6) VHF: Could be a distration when this close but may have been used effectively if employed sooner.

So what am I missing? /forums/images/graemlins/confused.gif
 
re: Poster: John100156

I would have thought turning to stbd through 180 and heading back to where you had come from based on the fact that this occured "about a third of the way accross" therefore shorter distance to travel on one engine and gets you out of the shipping lane.
 
Re: total rubbish

[ QUOTE ]
*WARNING* "Clever calcky thing" (i.e. simple mental arithmetic) coming up.
The container ship is a mile away, doing 24kts, overtaking the motor boat doing 9kts. At a closing speed of 15kts it will be past you in 4 minutes, during which you will have travelled 0.6miles to the west.
If we say (for the sake of argument) that this is happening 6 miles from your original destination, you could then reach your intended destination by steering 170 instead of your original 180. And (I did need a calculator for this bit) the distance to go would be 6.03 miles instead of 6.0 miles.

[/ QUOTE ]

But what about the cargo ship doing 12 knots? When you've done your 4 minutes heading west, he'll be 0.8M behind you, and when you then turn south you'll pass about 0.6M in front of him, giving you 3 minutes if something goes wrong. No great shakes, and i'd do it (in a fully functioning boat), but not the safety first, second and third approach that was being reccommended, and certainly not as safe as passing behind it. If you let this ship overtake you as well before turning, which I think was the proposed solution, then my original calcs apply.
 
Re: re: Poster: John100156

Yes - but it does not say where he came from, it could have been a buoy in a bay with no port/facilities! Hence my assumption that he had already decided that his current course was the best route to a safe haven to repair his boat /forums/images/graemlins/confused.gif!
 
Re: re: Poster: John100156

On that basis, i'd go with your suggestion turn to stbd through 360 and pass behind both and continue on original course.

I had assumed left home port.
 
Re: total rubbish

My thought is simply the amount of time we are discussing. If we take indefinitely, then Tony's YM suggestion is going to take this skipper to another continent!
So, I think people are suggesting what course to take to avoid the danger- ie 180 and head north....(not how to get home)
What happens next will be next months WNS /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif This will include berthing,lay-up, insurance claim, engine re-build, missing shaft anodes,re-launch, only to find two approaching commercial vessels of the port bow, and Bill Murray on deck.
Sorry but you are WAY ahead of the game !!
 
Re: total rubbish

[ QUOTE ]
Aww, come on JFM.. he asked someone more knowlegeable than himself, and said thats what the trained person suggested, which must count for something, and I think its OK for Tony to have mentioned that it was YM (as opposed to who-knows-who) Many of us would prefer the added safety of heading north, but maybe thats a degree of safety that isnt necessary as the first step. After all, its up to the skipper. People here can make their own judgement, surely.
The point of these scenarios is to show possible solutions. Running parallel could be a viable solution, I reckon, depending on other criteria that you would judge at the time.

[/ QUOTE ]

Sure. I agree the point is to show possible solutions, and once that's been done there's nothing wrong imho in the 90deg camp having a spat with the 180deg camp. It's a forum, innit?! "Trained" person counts for something of course. I was just specifically taking issue with TJ's apparent position which was that the YMI ticket per se puts YMI at the top of the pile so far as the correctness of nav views are concerned.
 
Re: total rubbish

Yep, evidently in this case I do.

Option 1= Sitting about waiting for a big ship to come along quite close by in five minutes who might have seen us and might not, while we're down to one engine, and also not calling him on vhf, that's another very excellent experty idea as well. Is crossing fingers allowed too? Has your expert heard of the Ouzo, I wonder, another boat quietly run down by cargo ship?

Option 2 = Not being there at all.
 
YMI story

I went on a course in the solent and near the needles the YMI guy mentioned at some point something along the lines of "it's usually ok for the novices around here, certainly if they stay inside the Safe Water Mark" . It didn't occur to him that the safe water mark is for big ships and the safe water is out there beyond the SWM, and not in here with the SWM marking the "deep end". I wonder if it was the same guy?
 
Exremely unlikely

Agreed. Just asd it was extremely unlikely that the engine fails just then. But it is a (remote) possibility, and there's still five minutes for more things to go wrong.

But if you aren't there at all, it's 100% impossible for him to ram you, hence that's a better solution.

Your YMI friend should be apraised of this clearly safer solution. Lots of very experty experts with plenty of qualifications have advised the wrong thing, in navigational and many other matters.
 
Re: Exremely unlikely

I have learned a lot from this discussion, if ever confronted with a similar situation in future I shall simply hand the helm over to SWMBO and go below and make a nice cup of tea!

Now the really important question, would I spill any at just 9 knots......... /forums/images/graemlins/blush.gif
 
I'm with Mapis on this. I don't like the stbd 90 turn or the stbd 180 turn. Also a 360 to stbd will take such little time and space, in a 45'er, that you will still be crossing ahead of the coaster and probably quite close behind the container ship, who will be really confused.

You're still 0.12 miles N of the coaster's track and if you simply stopped dead, you'd have to wait at least 5 minutes before it crosses. I would turn onto a heading of ~080 degrees or maybe 070 (to increase the lateral separation) and go behind the coaster's stern when it's clear. This gets you out of the way and avoids losing more time than necessary to your destination.

The turn to 080 can be either a 260 starboard turn or a 100 port turn. Bearing in mind that, in a boat this size, your 260 turn would be completed before anyone on the coaster has registered what's happening, I'm not sure what the difference is, in practice.
 
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